1. Technical Field
The present invention relates to a method of forming a film pattern, a film pattern, a device, an electro optic device, and an electronic apparatus.
2. Related Art
A semiconductor device (device) has been formed hitherto such that circuit wiring in which a thin film pattern (film pattern) composed of a conductor is disposed, an insulating film and the like to cover the circuit wiring, and a semiconductor layer are stacked on a substrate. As a method of forming this thin film pattern, a so-called inkjet method is known, in which a droplet of a functional liquid containing a material for forming a film as a solute is discharged from a droplet discharging head, and the functional liquid that has landed is dried so that the solvent is removed from the functional liquid, thereby forming a thin film pattern. In the inkjet method, a recess having the same planar shape as the thin film pattern is formed by forming a bank on a substrate so as to surround a region in which a thin film is to be formed. Further a functional liquid is discharged towards the recess and then the functional liquid that has landed on the recess is dried, and as a result, a desired thin film pattern can be formed.
In recent years, as the density of a circuit constituting a semiconductor device has become higher, for example, there has also been demands for finer wiring and thinner wires. To meet the demands, it is proposed that a functional liquid is discharged into a region for wiring formation partitioned by a bank with the fine width by the above inkjet method so as to form fine wiring.
At this point, it is desirable that a functional liquid be selectively discharged (placed) into the wiring foundation region alone. There is therefore a technique where a lyophobic treatment is performed for the surface of a bank to partition the wiring formation region mentioned above, and a lyophilic treatment is performed for the other parts, for example, the top of a substrate that will be the wiring formation region. When a functional liquid is discharged into the above wiring formation region, the entire functional liquid is poured into the wiring formation region even though part of the functional liquid is discharged into the top surface of the bank. Fine wiring (film pattern) is thereby formed.
Here, if the difference in the wettability (affinity) to the functional liquid is small between the lyophobic part for which a lyophobic treatment has been performed and the lyophilic part for which a lyophilic treatment has been performed, droplets placed on a bank might be repelled outside the bank not to spread in a wet state in the above wiring formation region. There is therefore a technique where the difference in contact angle with the functional liquid between the bank (lyophobic part) and the substrate (lyophilic part) is 40 degrees or more so that droplets that have landed on the bank reliably spread in a wet state in the above wiring formation region (see JP A-2004-363560, for example).
With the control of the contact angle as described above alone, however, when a droplet is discharged onto the bank and poured into the wiring formation region (pattern formation region) partitioned by the bank, a trace of the droplet landing still remains on the bank. At this point, if the functional liquid has conductivity, the landing trace of the droplet on the bank also has conductivity causing the wiring in the wiring formation region to be conductive with the landing trace. Then, contact with the landing trace on the bank might result in a short-circuit between wires formed adjacent with each other. The reliability of the wiring would therefore be reduced.